The development goals of oil fields under the PSC contract model overseas are different from those of domestic oil fields, which prioritize production. For overseas oil fields developed under the PSC contract model, economic benefits are the primary consideration, with all decisions made based on economic efficiency. Therefore, during the entire life cycle of development of such oil fields, the calculation of economic boundaries at key nodes is particularly important. This includes the well pattern density boundary, initial production boundary in the early stage of development, as well as the cumulative production boundary of individual wells, well shut-in boundary, and production scale boundary of the oil field in the late stage of development. All these require scientific decision-making to ensure the maximization of oil field benefits. This study has developed economic boundary models for five key decision-making nodes in the development of overseas oil fields under the PSC contract model and calculated the economic and technical boundaries of two typical blocks in the T oil field. By comparing with the predicted indicators of the development plans of the typical blocks, it provides an important basis for reservoir production and operation decisions at different development stages of oil fields under the PSC contract model. The research results have been widely applied in the actual production of a certain oil field and achieved good results..